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931.
Wei‐Ping Su Mao‐Chun Hong Rong Cao Jia‐Bao Weng Zhong‐Yuan Zhou S. C. Chan Albert 《中国化学》2001,19(9):817-821
The supramolecular silver(I)‐thiolate complex [Ag(μ2‐SC4N2H4)2(SCN)]n has been prepared from the reaction of AgSCN and pyrimidine‐2‐thiol in DMF. X‐ray diffraction analysis shows that the supramolecular structure exhibits one‐dimensional chain through the secondary Ag‐S interactions and the chains are further linked by strong hydrogen bonds to form a three dimensional network. The luminescence effect from the silver‐centered state of S→Ag LMCT in solid state is different from that in solution due to the secondary Ag‐S interactions. 相似文献
932.
933.
Lili Bao Xiaoge Qu Haimei Chen Xiaoli Su Shouzhuo Yao Wanzhi Wei 《Mikrochimica acta》1999,132(1):61-65
A method for determination of lysozyme with a Bulk Acoustic Wave (BAW) viscosity sensor is presented. It is based on the
bacteriolytic action of lysozyme on Micrococcus lysodeikeicus (M. lysodeikeicus) and the response of the sensor to the viscosity and density change of this process. There was a good correlation between
the frequency shift and the concentration of lysozyme in the range 10–100 μg/ml. The content of lysozyme in human saliva was
determined by this method and the results obtained were in good agreement with those from the conventional turbidimetric method.
This method has an advantage over the conventional turbidimetric method in that the amount of sample needed is smaller, the
procedure is simpler and the concentration range of the bacterium suspension which can be used in the detection was extended.
Received September 11, 1998. Revision March 15, 1999. 相似文献
934.
935.
热处理和紫外辐射对DNA影响的拉曼光谱研究 总被引:11,自引:2,他引:9
检测了鲕鱼精DNA纤维和经过40℃,91℃,200℃加热处理的拉曼光谱。研究结果表明,在熔融温度以下热处理对DNA构象的影响是轻微的,在熔融温度以上则随温度的升高,对DNA分子结构的影响有破坏也逐渐加剧,首先受影响的是腺嘌呤和脱氧核糖。 相似文献
936.
The structure of inherent nodal surfaces of four-boson systems has been investigated. The most probable structures for each
low-lying state have been found. A number of predictions on the structures of individual states and on the systematics of
the spectra have been found.
Received July 18, 1996; revised March 15, 1997; accepted in final form September 30, 1997 相似文献
937.
研究了球型平移网络对周期函数的逼近问题.文章首先将基函数eimx分别表示成为两种球型平移网络.进一步,将有关多重Fourier级数的Bochner-Riesz平均表示成为球型平移网络的形式.在此基础上构造出了两类球型平移网络序列,并借助于有关Bochner-Riesz平均对Lp空间中函数的逼近结果给出了这两类球型平移网络序列在Lp空间中的逼近阶. 相似文献
938.
939.
A study of irradiation in the treatment of wastewater 总被引:5,自引:0,他引:5
A grafting copolymer of starch and acrylamide was prepared by 60Co-γ pre-irradiation. After purification, the copolymer was modified by a cationic reaction to form a cationic copolymer. The structure of the cationic copolymer was identified by IR and NMR spectroscopy. Using the industrial and sanitary municipal wastewater from the Factory of Wastewater Treatment of Gaobeidian in Beijing as the study sample, three-treatment methods: flocculation deposition, flocculation deposition combined with γ irradiation and the direct irradiation were carried out. COD was applied to evaluate the treatment effect. The preliminary results show that the method of flocculation deposition combined with γ irradiation was effective than the other two. 相似文献
940.
A computational procedure for carrying out calculations on three-electron atomic systems in hyperspherical coordinates is presented. By adopting an adiabatic approximation, the solution of the Schrödinger equation at a fixed hyperradius is reduced to the solution of a set of coupled partial differential equations involving the two hyperangles. The derivation of such a set of coupled equations is explicitly illustrated. 相似文献